1,721,650 research outputs found
A novel stochastic method to dispatch microgrids using Monte Carlo scenarios
Full text linkStochastic operating strategies have proven to achieve cheaper resource scheduling both in large power systems and microgrids, but suffer from high computational requirements with respect to traditional deterministic approaches; therefore, using stochastic formulations in advanced infra-daily operating strategies is quite challenging, especially in isolated energy systems with limited computational assets. This paper proposes a dispatching methodology for microgrids based on a novel two-stage formulation that decomposes the stochastic problem into several deterministic subproblems, whose solutions are afterwards aggregated by the aggregator using simulations and a cost-based rule. In the first stage, every subproblem is solved, then each optimal dispatching is simulated in the second stage to evaluate the corresponding expected operating cost, which is used by the aggregator to select the final optimal scheduling. When compared to traditional methods for a rural microgrid in Uganda, the proposed approach not only achieves interesting savings in operational costs, up to 5%, but also sharply reduces the computational requirements, even more than 5–100 times with respect to traditional stochastic approaches. The paper also proposes a review and first classification of this kind of methodologies, to highlight the novelties of the approach
Giudizi critici e dialettici sulla Geomatica e la Geomatica Applicata: "Non c’è niente di buono o cattivo, è il pensiero a renderlo tale".
No full textHigh-frequency electrical stimulation promotes reshaping of the functional connections and synaptic plasticity in in vitro cortical networks
No full textHigh-frequency electrical stimulation (tetanus) promotes global synaptic potentiation in dissociated cortical networks coupled to multi-electrode arrays (MEAs). Since little is known about the functional changes induced by this protocol, this work aims to investigate the statistical dependences between the time series (i.e. functional links) of the network nodes involved pre- and post-tetanus. Specifically, we first show a strong reshaping of the functional connections induced by the stimulation and possibly associated with the global plasticity. Then, we find that about 30% of the nodes linked before and after electrical perturbation show high-connectivity degree (9 links), occupying a central role in the neuronal communication. Finally, we observe that these functional units drive the global network plasticity showing more synaptic potentiation than the other nodes involved in the connectivity reshaping
Distributed vs. centralized generation: Advantages and drawbacks
No full textThis section analyses the main benefits and drawbacks of conventional centralized generation and of the new, distributed architecture of power systems, discussing first of all the reasons for this change of paradigm. Distributed generation involves primarily, but not exclusively, crowds of small-scale renewable power plants connected to low-medium voltage networks, which is a huge breakthrough toward environmental sustainability, and beyond that an epochal challenge for system reliability and security. The intermittent and scarcely predictable nature of such sources, in fact, is highly demanding for power balancing and requires the traditional “fit-and-forget” approach to be quickly substituted by a real integration of dispersed generation into the system perspectives and needs. This section also details how flexible resources like energy storage devices and dispatchable distributed generators can contribute to power quality and to the secure operation of the power system, especially if involved in new market schemes. Finally, a quick review of operational and sizing criteria of off-grid configurations is provided
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Il ritorno delle foreste e della natura, il territorio rurale. Atti della XXIII Conferenza Nazionale SIU DOWNSCALING, RIGHTSIZING. Contrazione demografica e riorganizzazione spaziale, Torino, 17-18 giugno 2021, vol. 07
No full text- …
